Pantani, who also claimed the Giro d'Italia in 1998, was dogged by accusations of doping until his death from a cocaine overdose in 2004 at the age of 34, while last month Ullrich argued that while he had indeed doped, he had not cheated.

"I did not take anything that the others did not take," said the winner of the 1997 race. "Cheating starts for me when I gain an advantage. That was not the case. I wanted to have equal chances."

A further 12 riders from the 1998 race produced samples which qualified as suspicious in the year that the Festina scandal rocked the race and the sport to its core.

Green jersey winner Erik Zabel was also on the list, while Frenchman Laurent Jalabert, a two-time winner of both the points classification and the mountain classification during his career, was also named among the 18 positives, despite pulling his team out of the Tour as the scandal broke.

Jalabert claimed that all riders were being labelled as cheats when large quantities of doping products were found in the car of the one of the Festina support staff by French police.

British rider Chris Boardman, who won the prologue at that year's race and wore the Yellow Jersey during the first stage, was not on either list.

The report had drawn criticism prior to its release, with the professional cyclists' union arguing that the destroyed samples are no longer available to be re-analysed.

"Publication of a list amounts ... to an accusation of doping without any means of defence," they said last Friday.

The revelation follows Lance Armstrong's 2013 confession to doping for all seven of his Tour de France victories between 1999 and 2005. His name was removed from the record books by the UCI in October 2012, with race organisers electing to declare that there was no winner during his seven-year domination.

Pantani is still listed as the official winner of the 1998 Tour, and Ullrich the 1997 edition.